From 2b0c96f71ff1f26617dd805cafa35bf9a29c5a60 Mon Sep 17 00:00:00 2001 From: Nadav Rotem Date: Fri, 2 Nov 2012 21:47:47 +0000 Subject: Scalar Bitcasts and Truncs are usually free git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167323 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/TargetTransformImpl.cpp | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'lib/Target/TargetTransformImpl.cpp') diff --git a/lib/Target/TargetTransformImpl.cpp b/lib/Target/TargetTransformImpl.cpp index dbbf37a7dd..4cd07cd6c3 100644 --- a/lib/Target/TargetTransformImpl.cpp +++ b/lib/Target/TargetTransformImpl.cpp @@ -213,6 +213,11 @@ unsigned VectorTargetTransformImpl::getCastInstrCost(unsigned Opcode, Type *Dst, // Handle scalar conversions. if (!Src->isVectorTy() && !Dst->isVectorTy()) { + + // Scalar bitcasts and truncs are usually free. + if (Opcode == Instruction::BitCast || Opcode == Instruction::Trunc) + return 0; + // Just check the op cost. If the operation is legal then assume it costs 1. if (!TLI->isOperationExpand(ISD, DstLT.second)) return 1; -- cgit v1.2.3-70-g09d2